Effects of threat and efficacy messages on expected adherence to decontamination protocols in an immersive simulated chemical incident: A randomized controlled experiment

Abstract

The UK’s Initial Operational Response (IOR) decontamination protocol requires that chemically contaminated casualties remove contaminated clothing (disrobe) and then apply water or absorbent materials to skin. The health‐protective efficacy of the protocol is predicated on casualties quickly accepting both the need to act and the fact that this protocol is an effective action. The aim of this study was to test whether adherence is affected by the presentation of information by first responders about the severity and likelihood of contamination (Threat) and the health‐protective efficacy of IOR procedures (efficacy). A double‐blind randomized controlled experiment (N = 132) with a 3x2 independent measures design (registration number: ISRCTN17886859) was used to assess the effects of threat and efficacy on behavioural expectations during a simulated chemical incident, presented as an immersive video. Results indicated that addressing the threat of contamination made participants more likely to expect themselves to disrobe were the situation real. Emphasizing the efficacy of protective action made participants more likely to expect themselves to apply absorbent materials to skin and had an indirect positive effect on disrobing expectations, mediated by efficacy perceptions. We recommend that first responders explicitly address the threat of contamination and efficacy of decontamination when communicating with chemically contaminated casualties.

Public behaviour in response to the COVID-19 pandemic: understanding the role of group processes

“… 32 Subsequent research has demonstrated that effective engagement with the decontamination procedure is also increased when casualties perceive the effectiveness of the measures. 33 …”

Mass Casualty Decontamination for Chemical Incidents: Research Outcomes and Future Priorities

“…Studies that have examined casualty experiences and behaviour during decontamination [ 42 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 ] have suggested the way in which emergency responders manage an incident will affect the nature of the relationship between responders and members of the public, influencing how members of the public behave [ 67 ] and effecting the outcomes from the incident. Specifically, if emergency responders manage an incident effectively, members of the public will identify with them around a shared goal of undergoing decontamination [ 63 , 65 , 66 ]; this will result in increased public cooperation and compliance during the decontamination process [ 62 , 63 , 65 ].…”

“…Responders should: Communicate openly and honestly, providing regular updates about the nature of the incident and the actions that they are taking. Providing this information increases perceptions that responders are managing an incident in a fair and legitimate way and increases public willingness to comply with decontamination [ 42 , 63 , 65 , 66 , 68 ]. Communicate in a health-focused way about the need for decontamination.…”

“… Communicate in a health-focused way about the need for decontamination. This includes explaining the nature of the threat (from contamination) and the efficacy of decontamination measures for reducing that threat [ 68 ]. This will ensure that members of the public understand the need for decontamination [ 61 , 63 ], and that they perceive the instruction to undertake decontamination as legitimate, thus increasing willingness to comply with decontamination instructions [ 42 , 62 , 66 , 67 ].…”

“…Providing clear, detailed instructions on how to complete dry decontamination has previously been shown to improve adherence to dry decontamination protocols (18). A recent novel development has been the use of an immersive virtual reality chemical incident scenario in a randomised controlled experiment, evaluating the impact of different messages emphasising the threat and severity of contamination and the effectiveness of IOR actions on willingness to follow responders’ instructions [ 68 ]. This study showed that messaging that emphasised both the potential threat of the contaminant, along with the efficacy of IOR protocols, resulted in greater reported willingness to disrobe and follow dry decontamination protocols.…”